Active Action Items
Mark comment on draft ms_v21.pdf, emailed to him on 2012-08-01
- Catherine work out an analytic model (what does all this mean?!?)
- ALL think about MWB comment about frame-to-frame variations in background effect the FWHM; CI overwhelms the variation;
- Eric maintain action items page
characterize non-IA-CTI gain changes in XIS with Perseus
- Eric send Bev Perseus event lists for PHA/PI reconstruction
- Bev reconstruct Perseus PHA/PI values and send back to Eric
- 20120209 - check out the plots in the Data Products page
- come up with some metric for constraining non-CTI gain changes (in IA); intercept of central pixel PH vs. y
- Bev fit central pixel PHAs for Perseus data
- like Catherine predicted, it's looking awfully hopeless (14feb12)
- actually, it's not looking hopeless after all and Bev will keep working on it (1mar12)
- still might be hopeless, but Bev believes it's possible to calculate CTI, but might not be interesting (might not constrain non-CTI gain changes); Bev will keep working on it (10apr12); perhaps we don't need this, summed pulseheight is better (31may12)
- Bev fit summed pulseheights in perseus data for a few Y regions, intercept of fit line should be ~ non-CTI gain change (actually non-CTI-in-IA change)
- Bev will overplot FI/BI, CI on/off intercepts on single plot, in terms of fractional change
- Bev will get linear fit to trend for CI on; this will be upper limit to non-CTI-in-IA change
- use Gehrels weighting
- Bev will change the y-axis
- Catherine will incorporate into the paper
- Bev recompute XIS gain/FWHM vs. COR2 fits for Catherine, but using COR2 and Gehrels weighting
- Bev check the COR2 = 11,12,13 fits visually to see if they are acceptable chi-by-eye-wise
- Eric will figure out the COR2 value during the XIS raw frame observations
- 20120716 – COR2 = 12.0-14.1 during the 10 raw frames; frame 2 is the one in the paper, and that has COR2=12.8
- Eric will try to estimate the error in CTI/FWHM values in COR bins (Bev will send him spectra)
- IDL gets about the correct uncertainties if weighted by 1/cts
- Bev will do this for all of the COR2 bins
- Catherine put errorbars on COR2 figures, and say that they're small if they are
- all think about why FWHM at COR2 10-14 are significantly different
- Catherine and Bev will refit everything using Gehrels weighting
- ACIS cal source gain and FWHM vs. time
- XIS cal source gain and FWHM vs. time and COR2
- XIS Perseus for non-IA-CTI measure
- Eric see if there is change in XIS BG with time on longer baseline than Tawa, modulo COR2
- 2012-09-14 seems to be for XIS1, count rate is decreasing @ 3% per year - see Data Products
- try all COR, extend energy to 5 keV, look at COR histogram w/ time
- BI different from FI, looking at hot pixels and charge injection trailing rows, look at Ni-K line ???
- Bev make example spectra for XIS BI, ACIS BI early in mission on one plot (or whatever she thinks is good).
- don't overlay fits. try on same plot or as multiple panels.
- use energy as x-axis, range 1-10 keV, linear X and Y axes.
- 2012-09-06 Bev showed samples and Catherine and Eric made suggestions for changes
- Catherine continue to write
- still need a general reference for radiation damage in CCDs
- "gain" decrease could include framestore CTI, confess
- use percent or fraction to express CTI and gain changes (not ADU or eV) (2012-07-27)
- more warnings, not representative of user data, unprocessed/uncorrected
all look at Fig 8 and think about interesting features to point out/annotate (rocket ships, framestore wackiness, etc.)--wait to see if this is appropriate in context of final text- Bev and Eric read what Catherine has written so far and comment, suggest places that need references (comments incorporated through 2012-05-22)
- Eric read paper and comment; especially section on changing XIS bg, and provide numbers for change (no figures)
- Eric make particle background spectrum plot
- Catherine incorporate particle background spectrum plot into paper
- future work
- think about ways to construct ground experiment to test on-orbit results
- use Co-60, tritium/e- source
- Bev will ask Steve about using CI to mimic particles
- can charge level be set on a pixel-by-pixel basis?
Completed Action Items
- ALL have an outline for Mark
- outline is sent to Mark (2011-01-28)
- here is a link to an attachment: Outline PDF
- 20100210--comments from Mark here
- Eric combine outlines
- Eric convert action items page
- ALL decide on common CTI metric (which grades, which pixels in island, which rows)
- use center pixels
- XIS cal source regions-
- both use all telemetered grades (minus 255 for XIS, minus 5 Bev grades for ACIS, S3 only uses g02)
- Bev will try restricting grades, esp. for BI
- 2011-05-05 decision to not pursue CTI metric for XIS
- Bev make CTI plots for XIS upper rows (1 month bins)
- 20110210Bev has IDL script set up, pixel fits (center pixel pulseheight and trailing pixel) are working for all detectors/quads, CTI calculation is not working completely
- Catherine replicate same plots for ACIS, pending Bev's results
- 2011-05-05 decision to not pursue CTI metric for XIS
- Catherine replicate existing Bev plot (monthly plots of FWHM, summed pulseheight centroid)
- 20110210--CEG has framework set up, waiting on flaky disk
- 20110217--CEG posted plots to Data Products
- 20110407--CEG made plots for IACHEC, For paper, want just combined plots, peaks (eV)/5894 eV – same y-range, widths in FWHM (eV)
- Eric add space for Leaky Buckets presentations (posters, talks slides) to Publications page (20110620--CEG)
- 20110407--CEG a few slides for IACHEC, summarizing our goals and what we're doing IACHEC slides
- We should talk about the mechanics of writing the paper. Does Eric keep a master copy and we send text and revisions to him? Do we post a master copy here that we can check-out to edit ourselves?
- Eric will keep master version of tex file, update wiki on occasion
- Bev and Catherine can borrow tex tarball for big jobs
- Catherine's Suzaku poster wishlist:
- Peak & FWHM vs COR for early (CI off) and late (CI on) for XIS1 and XIS3 (Thank you Bev!)
- Catherine send to Bev copy of her line fitting (20110607, and the forgotten bits on 20110620)
- Catherine show that line centroid is good proxy for CTI (20110621--CEG posted to Data Products)
- then we can just use that and not worry about XIS CTI metric
- Catherine spot check line fits (20110621--CEG convinced that results are consistent between different bkg levels and src count rates)
- Catherine convince herself that ACIS QE drop goes away with CTI correction (20110622--mostly goes away. QE drop goes from ~12% to ~3% over 11 years)
- Catherine find the cut-and-paste text from previous ACIS papers, send to Eric (20110705--sent some text from SPIE2007 paper)
- Catherine make half-life plots
- 20110324--CEG posted plots to Data Products
- Bev find the cut-and-paste text from previous XIS papers, send to Eric
- Catherine make XIS half-life plots using Bev's data which use Catherine's fitting method (20111018)
- 20111028--CEG doesn't make much difference, XIS1 line flux is still weird
- Bev make new plots of line center and FWHM vs. COR using Catherine's fitting method
- from 2008 paper, will look for script that made them and verify that it's still flat; revisit with non-XIS2 devices
- 20110504--bev posted xis1 & xis3 plots for 201101 to Data Products
- Catherine will think about equivalent for ACIS, flat FWHM, but are FI wiggles due to background wiggles? compile bkg data in same time bins
- 20110816--actually confirmed this a while ago and forgot to update, the FI wiggles are not correlated with the background, ACIS FWHM is not strongly sensitive to sacrificial charge
- Eric begin latex document for A&A (downloaded A&A template)
- Eric look for pictures of XIS for schematic
- Eric look into A&A photo and color policies
- color figures are E250 each for 1 or 2, E180 each for 3 or more; should be in CMYK, not RGB; online (PDF?) color figures are free, but will be greyscaled in print version
- page charges are E100 per printed page
- no specific photo policy
- Eric look into figure format (titles, fonts, etc.) policy
- no specific policy about title, but looking at several papers, none of the figures have them
- no specific policy about fonts, we should just be consistent
- ALL think about whether to include trailing charge info for both instruments
- not very fruitful; XIS is limited to the top of the array, so hard to separate trailing charge from normal event splitting; also SCI will complicate this
- Catherine. Look at Bev's plots (http://space.mit.edu.ezproxyberklee.flo.org/XIS/monitor/ccdperf), get a sense how ACIS would look on the same kind of plot. Qualitatively, how much does trailing charge matter. (20111031--CEG, plots on data products page)
- Bev make gain/FWHM vs. COR plots for XIS3, Oct+Nov 2006 (20111028--done)
- see if it's as good as XIS2 previous plots
- send data to Catherine for paper figures (20111028--done, figures to be added to tar ball shortly)
- Catherine change fig captions for gain/FWHM vs. COR; data are for ~ 1 month (or 2) straddling CI turning on, and for XIS2 (or XIS3)
- Catherine send paper appropriate figures to Eric (20111031--CEG In progress. See Data Products for new versions and one new one) and recipe to bev.
- bev will give catherine pre-launch CTI values for xis.
- from http://space.mit.edu.ezproxyberklee.flo.org/XIS/about/lamarr_spie_5501_385.pdf Figure 4; BI (8c2) = 0.55, FI = 0.30-0.35
- Eric make schematic diagrams (20111121--EDM, see Data Products Item 9)
- Eric edit ACIS schematic to make cal source regions squares (for XIS too?)
- Eric add CI rows and coord axes and move S3 aimpoint
- Eric fix crappy lines and circles (20111220--EDM done)
- Bev confirm that ACIS and XIS are using the same high energy reject metric; time units and spatial area? what is being rejected on-board?
- XIS uses only cal source area, ~ 9-10% of full 1024x1024
- Bev rejects summed event PHA of >= 3750 on ground to match ACIS rejection; but some single pixels are rejected on board XIS, possibly below 3750
- seems no way to compare XIS rejection to ACIS
- also dependence on input energy spectrum
- Bev will look for XIS frame data to see how well the background metric matches that of ACIS
- Bev will grab raw frames for the paper to show background, and bias-correct; XIS BI & FI, CI on & off, ACIS BI & FI
- Bev add labels to colorbar (horizontal), add frames around each FOV, fix ACIS bias levels
- Bev will upload final frame EPS files and colorbar to wiki
- Eric choose best Bev frame images
- Eric help Catherine with latex layout of raw frames and colorbar
- Catherine change A4 formatting to Letter in dvips
- 2012-01-10 probably actually an A&A issue
- Eric tell Bev which raw frames to annotate
- Bev add "ACIS FI" etc. to upper right corner of the four raw frame PS files
- Bev search for reference on XIS Lesser process for thinning BI
- Section 4 of Mark's 2004 spie paper (available locally at http://space.mit.edu.ezproxyberklee.flo.org/XIS/about/bautz_5501_14_4june.pdf) discusses this improvement. He references M. Lesser and V. Iyer, “Enhancing the back illuminated performance of astronomical CCDs,” Proc. SPIE 3355, pp. 446--456, 1998. B. E. Burke, J. A. Gregory, A. H. Loomis, M. Lesser, M. W. Bautz, S. E. Kissel, D. D. Rathman, R. M. Osgood, M. J. Cooper, T. A. Lind, and G. R. Ricker, “CCD soft-X-ray detectors with improved high- and low-energy performance,” IEEE Trans. Nuclear Science in press, 2004.
- Catherine add comment in paper or Table 1 about different BI processes. 2012-02-01 added comment in v11. it's pretty vague but it's there, still needs an XIS reference
- Catherine add paragraph to end of Section 2.2? on how we're only analyzing parallel CTI, serial CTI (define them) is low except for ACIS BI, because of different BI process; therefore we're not talking about serial CTI cause it hasn't changed
- 2012-02-01 added to Sec. 2.1 in v11
Retired 2012-09-13
- Bev will plot and understand HE rejects for XIS vs time and COR; do BI first
- will probably not help for paper; use cumulative charge above 100 ADU instead
- Bev check whether she used COR or COR2; will try to get COR2 via ehk files
- Catherine continue to think about temperature dependence of CTI (finish writing up)
- Catherine (with Bev input) write text explanations of data processing to all figures in paper
- Catherine rename bibtex file to leaky bucket specific
- 2012-02-02 v12 of paper uses leakb.bib
- Bev look bright Earth data O line w/ time to look for non-CTI gain changes
- decided it's the wrong energy, not sure about light leak, use Perseus instead
- Bev will count particle events on raw frames (or rather pixels above some threshold that she will choose)
- Bev showed cumulative charge vs. threshold; will determine value for 100 ADU threshold for all frames, and that will give estimate of how BG varies
- Bev will make plots of spectra around Mn Kalpha for XIS3, SCI off and on, 2006-10 to 2006-11
- Catherine look at Tawa et al 2008 paper to see time- (COR-) dependence of XIS background
